1. Field of the Invention
The present invention relates to a transport device comprising a traveling holding member which can travel while holding a storage container for storing disc-shaped substrates such that the substrates are layered in a vertical direction, said storage container having an opening formed in one side thereof for inserting and removing the substrates, and a move out prevention mechanism that prevents the substrates from moving out of the opening of the storage container held by the traveling holding member.
2. Description of the Related Art
Transport devices such as one described above transport a storage container by causing a traveling holding member holding the storage container to travel, and include a move out prevention mechanism for preventing substrates from moving out of an opening of the storage container when the traveling holding member is traveling.
And, an example of such a transport device in accordance with a conventional technology includes one in which its move out prevention mechanism includes a contacting member that is movable between a contact position at which the contacting member is in contact with side faces of the substrates stored in the storage container, and a spaced apart position at which the contacting member is spaced apart from the side faces of the substrates. And the contact position of the contacting member is set such that the contacting member extends from a location inward of an opening side end portion of the substrates stored in the storage container to a location outward thereof in a direction along which the substrates are inserted and removed. (See, for example, JP Publication of Application No. 2001-077170.)
Thus, the transport device can travel while preventing the substrates from moving out of the storage container by causing the traveling holding member to travel with the contacting member being in the contact position. And, damage to the substrates caused by the substrates contacting the contacting member can be prevented before such damage occurs by moving the contacting member to the spaced apart position, when transferring the storage container held by the traveling holding member to the container transport target location for the container by means of transfer means provided to the transport device or an external transfer means.
In the conventional transport device described above, when the contacting member is moved to the contact position, the contacting member is positioned such that it extends from a location inward of the opening side end portion of the substrates to a location outward thereof in the direction along which the substrates are inserted and removed. With the contacting member extending to a location outward of the opening side end portion of the substrates when the contacting member is moved to the contact position as described, the width of the transport device, in the direction along which the substrates are inserted and removed with the contacting member having been moved to the contact position, tends to be greater than otherwise by the amount that the contacting portion extends outwardly of the opening side end portion of the substrate, making it difficult to reduce the dimension of the transport device in the direction in which the substrates are inserted and removed during the travel of the transport device.